Spraying device for pastelike material with shutoff valve means for the material

ABSTRACT

A spray device or gun utilizing compressed air as the carrier for the material to be sprayed, comprising a body having an air passage system connecting the air supply to the air nozzle, and a material passage system connecting the supply of the material to the material nozzle. A pressure-reducing valve is interposed in the air passage system to reduce the spraying air pressure. A shutoff valve is located in the material passage system to stop or permit flow of material. The shutoff valve is provided with pressure-responsive actuating means, the means being connected to the air passage system whereby when air pressure is present the shutoff valve is kept in its open position. The passages of the material passage system are so arranged that the shutoff valve first closes the passage leading from to the material nozzle means, and thereafter closes the passages leading from the material supply. This closure arrangement maintains the material nozzle and its passage clear from drippings upon air shut off.

llttite Staes atet [72] Inventor Gunter Glrortert 3,482,781 12/1969Sharpe 239/41 1 X Mettmann, Germany 3,064,862 11/1962 Sanders v. 239/41]X l2] 1 2 g z gg 1970 Primary ExaminerM. Henson Wood. Jr. [22] flyAssistant Examiner-Michael Y. Mar [45] Pmemcd Attorney-Abraham A.Saffitz l 73 I Assignee Berglsche Metallwareniabrlk Dlllenherg &

Co., KG I Grunenr Germany ABSTRACT: A spray device or gun utilizingcompressed air as l l Prlomy y 30, 1970 the carrier for the material tobe sprayed. comprising a body Germany having an air passage systemconnecting the air supply to the l l l P 19 27 574-2 air nozzle. and amaterial passage system connecting the supply of the material to thematerial nozzle. A pressured' l"t sd'tha' t t 1 1 WITH SHUTOFF VALVEMEANS FOR THE the material passage system to stop or permit flow ofmaterial. MATERIAL The shutoff valve is provided with ressure-res onsiveactuat' P P 8Clalms4Drawmg ing means, the means being connected to theair passage [52] US. Cl. 239/337, ,system whereby when air pressure ispresent the shutoff valve 239/296,239/4l1,239/4l2, 251/62 is kept in itsopen position. The passages of the material [51] lnt.Cl. B05!) 7/32passage system are 50 arranged that the shutoff valve first [50] Field0! Search 239/337, closes the passage leading from to the materialnozzle means. 407, 410, 41 l.4l2,4l3, 296; 251/61.1, 62, 331 andthereafter closes the passages leading from the material supply. Thisclosure arrangement maintains the material nozl l References Che! zleand its assa e clear from drippings upon air shut off.

P g UNITED STATES PATENTS 3,194,502 7/1965 West 2 9/41 l 48 l i 5 SPRAY33 MATERIAL PATENTED unv 2 3 Ian SHEEI 1 OF 3 FIG. 1

mvnu'ron GUNTER GRONERT BY 9610mm Kl. $4 1M ATTORN EY PAIENTEnnuv 23I87! 3.622.078

sum 3 or 3 u v ENTOR GUNTER GRONERT BY I051 Mm [q ATTORNEY Thisinvention relates to sprayer devices wherein compressed air is used as acarrier for paste or slurry type material to be sprayed.

Prior art spray devices are usually equipped with three hoses, one forthe compressed-air line, a second for the material to be sprayed, and athird for carrying air to the material shutofi' valve. In addition, tothe numerous hoses, there is a possibility that upon a bursting orshutoff of the spray airhose, the spray material would still continue tobe squeezed out of the spray device as a spray or a dripping.

Another disadvantage of the prior art spray devices is that the airpressure reducing value is located remotely from the spray head and isnot very accessible for adjustment.

An object of this invention is to provide a spray device provided with aspray material shutoff valve in the body of the device and responsive tothe pressure in the spray air passage system in the body, therebyeliminating one of the above-mentioned three hoses.

Another object is to provide a pressure-reducing valve located in theair passage system in the body of the device, with easily accessiblepressure-adjusting means on the body.

A further object is to provide a sequence of passage closings by theshutoff valve so that all trapped spray material is expelled upon feedair shutoff or failure, whereby the nozzle means is kept free ofmaterial dripping.

A further object is to provide an air passage system having a largespace capacity whereby a residual supply of air is stored after the flowof feed air is terminated. The air nozzle means is connected to thespace whereby sufiicient carrier air is supplied for the materialremaining in the nozzle and its adjacent passage after the shutoff valvecuts ofi the flow of material.

Further objects and advantages will be apparent from the followingdescription and accompanying drawings wherein:

FIG. 1 is a front perspective view of the spraying device;

FIG. 2 is a sectional and partly diagrammatic view of the air passagesystem;

FIG. 3 is a sectional and partly diagrammatic view of the spray materialsupply system; and

FIG. 4 is a detailed view of the shutoff valve in its closed position.

The spraying device or gun I has the usual compressed-air feedline 2 andthe material to be sprayed feedline 3. While it is obvious that anymaterial may be sprayed with the disclosed device, such as powderedmaterial, paint, liquid plastic, etc., the device is especiallyadaptable to spray a material in the form of a paste, slurry or thelike. One of the purposes of the device is to spray a pastelike materialfor grinding or lapping purposes in grinding machines. The term spraymaterial" will be used in the following specification and claims tocover any sprayable material.

Device l comprises a body 4 to which fed lines 2 and 3 are attached atone end, and to which the outlet nozzle means are attached at theopposite end. The nozzle means consists of a spray material nozzle 5, aspray air nozzle 6 having its orifice concentric with that of nozzle 5and further having two additional air orifices 6a, laterally locatedwith respect to the concentric orifices. Air feedline 2 and materialfeedline 3 are connected by conventional threaded fittings 7 and 8,respectively, to the passage systems within body 4. An adjusting means 9for pressure-reducing valve 10 (FIG. 2) extends from one end of body 4.A pressure gauge 11 to indicate the reduced spray air pressure ismounted on body 4 in a position where it can be visually observed while,turning pressure'adjusting means 9. A casing depends from body 4 forhousing a shutoff valve mechanism designated by character 12. A spraymaterial flow regulating valve I3, in the form of a needle valve, has aknurled manipulating portion extending from top of body 4.

FIG. 2 is a sectional view, somewhat diagrammatic of body 4 toillustrate the air feed passage system and the pressure reducing valve10 incorporated therein. The compressed air is delivered to passage 15.A passage 14 leads from passage 15 to passage means 41-42 (FIG. 4) toact upon the pressureresponsive means of shutoff valve means 12 to keepthe valve in open position as long as air flows to the spraying device.Pressure-reducing valve 10 comprises a valve seat body 16 having a seat17 which cooperates with movable valve head 18 seating thereon. Valve 18has a clearance space 8 within the bore in which it slides, or someother communicating means may be provided whereby air may flow frompassage 15 through the interior of valve seat 17, when valve head 18 ismoved away from the seat. Valve head 18 is biased by light spring 19towards seat 17. Valve 18 is biased away from the seat by adjustablespring 22 which acts on rod 20a through plates 20 and 21 and adapterpiece 24. A diaphragm 23 is clamped between plates 20 and 21. Thecompressive force of spring 22 is adjustable by threaded means 25-26.

In operation, air flowing past open valve means 17-18 acts on diaphragm23 to move it to the right. When the pressure of the air attains thedesired reduced valve set by adjusting means 26, diaphragm 23 movessufficiently to the right to throttle the flow of air through valve seat17 to attain the desired pressure drop. The final position of value headI8 is such that it throttles the airflow to reduce the pressure to thedesired degree, which reduced pressure is indicated by pressure gaugeII.

The feed air under reduced pressure flows through passage 27 into anannular chamber or space 29. Chamber 29 is closed off by air nozzle 6which is fon'ned in a body 30 which fits into the end chamber 19. FIG. 2shows the nozzle means in an exploded position. Noule 6 is held uponbody 4 by a threaded ring 31 which engages threads 32 formed on body 4around the open end of chamber 29.

The material to be sprayed, which may be in the form of a paste or thelike, is fed into the material passage system by hose 3 connected tobody 4 by fitting 8 which enter a passage 33 of the system. A formation34 within body 4 connects passage 33 to material feed-in passage 35. Asshown in greater detail in FIG. 4, passage 33 terminates at formation 34in a grooved outlet part 36. The inlet port 37 of feed-in passage 35 hasan annular raised lip surrounding it: the result is that parts 36 and 37are not in the same plane, but port 37 extends farther into formation 34than port 36.

Shutoff valve means 12 comprises a seal and closure diaphragm 39 and aplug member 40 whereby the casing containing valve means 12 is securedto body 4. The feed air reaches valve means 12 through passage 14connected to feed passage 15 FIG. 2) and passage means 41 and 42connected to passage 14. Diaphragm 39 functions as the shutoff valve. Itis actuated to its open position of FIG. 3, that is, the positionwherein passages 33 and 35 are in communication, by air from passage 42flowing into chamber 43 and acting on pressureresponsive meanscomprising cup piston 44 sealing the open end of the chamber 43. Piston44 is connected to rod 45 which is in abutting relation with a domedmember 46. Member 46 engages diaphragm 39. The air pressure on piston 44permits diaphragm 39 to assume its unstressed position to thereby opencommunication between passages 33 and 35.

Upon a failure of feed air or a certain reduction thereof, a spring 47which may be adjusted by means 49 urges piston 44, rod 45, and member 46upwardly to thereby force diaphragm 39 into the position of FIG. 4wherein ports 36 and 37 are closed. It should be noted that in itsupward shutoff movement, diaphragm 39 first engages annular lip 38thereby closing material feed-in port 37 before port 36. This sequenceof port closing permits diaphragm 39 to immediately cut off port 37 andthereafter force any spray material in formation 34 into still openmaterial supply passage 33. Although the air feed supply is cut off orvented from fitting 7 and passage 15, there is sufficient residual airin the passages and in space or chamber 29 to atomize and spray theresidual material left within passage 35 and nozzle 5 after shutoffdiaphragm closed port 37. Thus, the arrangement of nozzle means 5. 6 and60 will cause the discharge of all the residual material, whichoperation results in clear and empty passage means and nozzle orifices.This arrangement eliminates the usual drippings and leftover material inthe nozzle and passage means of the prior art spraying devices.

The passage means 35 to nozzle 5 runs in straight lines, with no blindbores or angles wherein air cushions could form, which would exertpressure in the spray material to move it and cause dripping thereof atnozzle 5, when the feed air is cut ofi.

To regulate the flow of spray material, adjustable needle valve 13 isinserted in the passage means 35 (HO. 3). A seal means, such as anO-ring 48, is provided on the stem of the needle to prevent leakage ofair and material.

Spring 47 is adjusted by means of screw means 49 to vary the openingwidth or flow area adjacent port 37. By varying the extent of theshutoff stroke of diaphragm 39, the flow area can be varied toaccomodate the consistency of the spray material. ln case of highlyfluid material, narrow opening width would be in order, that is, thedistance between diaphragm 39 and lip 38 would be slight.

Although a certain preferred embodiment of the invention has beendiscovered for purposes of illustration, it will be evident that variouschanges and modifications may be made therein without departing from thescope and spirit of the invention.

What is claimed is:

l. A spraying device comprising a body, an air fitting secured to saidbody and adapted to be connected to a compressed air supply, a spraymaterial fitting secured to said body and adapted to be connected to aspray material supply, an air discharge noule means, a spray materialdischarge nozzle means cooperating therewith first passage systeminterconnecting said air fitting and said air nozzle means, apressurereducing valve in said first passage system to reduce thepressure of the air flowing from the fitting to the air nozzle, a secondpassage system interconnecting said spray material fitting and thematerial nozzle, said second passage system comprising a formation intowhich a first material feed passage means enters and from which a secondpassage means leads to the spray material nozzle, the ports of saidpassage means entering said formation in different planes, a shutoffvalve means in said second passage system movable to a closed positionto prevent flow of material therethrough or to an open position, saidshutoff valve having a closure member entering said formation to firstclose off the port of said second passage means and thereafter closingoff the port of said first passage means, pressure-responsive means toactuate said shutoff valve means, and passage means connecting saidfirst passage system to said pressure-responsive means to move saidvalve to said open position.

2. The spraying device as claimed in claim 1 wherein said closure memberis a flexible diaphragm capable of assuming the shape of the formation.

3. The spraying device as claimed in claim 2 wherein the ports of thesecond passage means has a projecting lip encircling it, thereby causingthe diaphragm to contact it before contacting the port of said firstpassage means.

4. The spraying device as claimed in claim 1 wherein said first passagesystem includes a relatively large space downstream of thepressure-reducing valve to which space the air nozzle means isconnected.

5. The spraying device as claimed in claim 4 wherein said air nozzlemeans comprises a central air orifice concentric with and encompassingthe orifice of the spray material nozzle, and additional air orificeslateral to said central orifice.

6. The spraying device as claimed in claim 1 wherein a flowregulatingvalve is inserted in said second passage means before the materialnozzle means.

7. The spraying device as claimed in claim 1 wherein saidpressure-responsive means comprises adjustable spring means to bias theforce of the feed air, and means connecting said spring means and saidclosure member to adjust the closing stroke of the closure member andthereby the flow area for the spray material.

8. The spraying device as claimed in claimed 1 wherein the secondpassage means if formed by a series of straight passages with no blindbores therebetween.

it k a a:

1. A spraying device comprising a body, an air fitting secured to saidbody and adapted to be connected to a compressed air supply, a spraymaterial fitting secured to said body and adapted to be connected to aspray material supply, an air discharge nozzle means, a spray materialdischarge nozzle means cooperating therewith, first passage systeminterconnecting said air fitting and said air nozzle means, apressure-reducing valve in said first passage system to reduce thepressure of the air flowing from the fitting to the air nozzle, a secondpassage system interconnecting said spray material fitting and themaTerial nozzle, said second passage system comprising a formation intowhich a first material feed passage means enters and from which a secondpassage means leads to the spray material nozzle, the ports of saidpassage means entering said formation in different planes, a shutoffvalve means in said second passage system movable to a closed positionto prevent flow of meterial therethrough or to an open position, saidshutoff valve having a closure member entering said formation to firstclose off the port of said second passage means and thereafter closingoff the port of said first passage means, pressure-responsive means toactuate said shutoff valve means, and passage means connecting saidfirst passage system to said pressure-responsive means to move saidvalve to said open position.
 2. The spraying device as claimed in claim1 wherein said closure member is a flexible diaphragm capable ofassuming the shape of the formation.
 3. The spraying device as claimedin claim 2 wherein the ports of the second passage means has aprojecting lip encircling it, thereby causing the diaphragm to contactit before contacting the port of said first passage means.
 4. Thespraying device as claimed in claim 1 wherein said first passage systemincludes a relatively large space downstream of the pressure-reducingvalve to which space the air nozzle means is connected.
 5. The sprayingdevice as claimed in claim 4 wherein said air nozzle means comprises acentral air orifice concentric with and encompassing the orifice of thespray material nozzle, and additional air orifices lateral to saidcentral orifice.
 6. The spraying device as claimed in claim 1 wherein aflow-regulating valve is inserted in said second passage means beforethe material nozzle means.
 7. The spraying device as claimed in claim 1wherein said pressure-responsive means comprises adjustable spring meansto bias the force of the feed air, and means connecting said springmeans and said closure member to adjust the closing stroke of theclosure member and thereby the flow area for the spray material.
 8. Thespraying device as claimed in claimed 1 wherein the second passage meansis formed by a series of straight passages with no blind borestherebetween.